Self-starting timing motor



Feb. 1, 1966 J. w. FARMER ETA!- 3,232,039

SELF-STARTING TIMING MOTOR 1 M N .t mR M e I EE m m A m Vw s NFE d .w F I Q 6 W O C m H M S mm 2 MM Y B Filed Oct. 8, 1962 A TTORNEYS.

Feb. 1, 1966 J.W. FARMER ETAL 3,232,039

SELF-$TARTING TIMING MOTOR Filed Oct. 8, 1962 2 Sheets-Sheet 2 mmmy mdE M d W6 on v A TTORNEYS.

$232,039 SELF-STARTING TIMING MOTOR James W. Farmer, 327 Perry Ave, and Ralph G. Eshleman, 174 Hostetter Lane, both of Lancaster, Pa.

' Filed Oct. 8, 1962,; Ser. No. 228,993

7 Claims. (Cl. 58-147) This invention relates to a timing motor and more particularly to an AC. or DC. electrically powered selfstartiug escapement controlled timing motor wherein the timing unit is in the form of a watch movement.

Various types of timing motors are known. In one suchtype the "oscillating balance and escapernent of a clock structure is used to control the run-down of a main spring driving the output. shaft. Devices of this type sometimes employ an automatic rewind arrangement wherein the main spring is rewound through the action of the movable armature of an electro-magnet. The main spring drives the output shaft through a suitable clutchirig arrangement and also actuates a rotary member which, after a certain predetermined run-down of the main spring, closes a pair of contacts, completing a circuit through the electro-magnet coil. Energization of the electro-magnet causes its armature to move, thus transmitting a rewind impulse'tO the main spring for the initiation of another cycle. Prior devices of this type have suffered from the disadvantage that in general they are relatively large and are not self-starting. i

The present invention provides a watch movement type timing motor including provisions for self-starting the balance system so that the unitis operative irrespective of interruptions in the power supply. The timing rnotor of the present invention may be used for visually indicating whether current is flowing in the circuit it monitors, for registering the accumulated time during which a current flows, whether continuously or intermittently, and for emitting periodic voltage pulses usable for monitoring the device itself or for controlling other electronic or electro-mechanical units. It'is' therefore a primary object of the present invention to provide a novel timing motor of substantially smaller size. i i

Another object of the present invention is to provide a novel, simplifier, self-startingarrangement for timing motors.

Another object ofthe present invention is to provide a :unit for indicating the accumulated time during which current flows in a monitored circuit.

Another object of the present invention is to provide an electrically powered self-starting timing'motor.

These and further objects and advantages of the invention will be more appare'ntupon reference to the following specification, claims and appended drawings wherein:

FIGURE 1 is an exploded view of a timing motor constructed in accordance with the present invention.

FIGURE 2 is a partial cross section showing the electro-magnet and movable armature of FIGURE 1;'and' FIGURE 3 is an exploded view of a modified timing motor constructed in accordance with the present invention.

Referring to FIGURES 1 and 2 the novel timing motor of the present invention indicate-d generally at comprises a pair of indicating hands 12 supported on a dial plate 14 and driven by way of a dial train 16. The dial train is driven by suitable means (not shown) from the center arbor 18 which is in turn coupled by conventional gearing to the third arbor 20.

Positioned above supporting plate 22 is a conventional watch movement 24 including a balance wheel 26. The balance wheel is modified by substituting several soft iron 3,232,939 Patented Feb. 1, 1966 screws 28 for the conventional gold screws. Or, if the balance wheel is a plain sc'rewless unit, the soft iron screws may take the form of soft iron slugs. A small electro-magnet 30 is mounted in such a manner that the projecting core piece 22 whose tip is cut off at an appropriate angle as indicated at '34 lies close to the balance wheel rim in a position suitable for attracting the iron screws 28 mounted on the balance wheel.

' The conventional watch movement need not be otherwise altered and the time train gears are conventional except that the center and third arbors 18 and 20, respectively, are modified. Both the center and third arbors are extended upward past the normal position of the train bridge of the watch and center arbor18 is pivoted in a special plate 36 while third arbor 20 is pivoted in a bracket 38 secured to the plate 36 by a screw such as indicated at 40.

Pivoted on the extension 42 of the third arbor 20 is a rotor 44 carrying a pair of weights 46 and 48. Adjacent the weight 48, the rotor 44 carries 'acontact button 50. 'Rotor 44also carries on its underside a post 52 to which is connected a flexible conductive wire 54 having its otherend connected to a post 56 on stationary plate 36. Rotor 44 is also provided with a member 58 defining a cam surface 60. A

Rotor 44 is freely rotatable about the third arbor 20 and'can absorb, store and transfer an appreciable amount of rotor energy. A similar mounting is provided for a second rotor 62 mounted on the upward extension of the center arbor 18. This second rotor includes a long arm 64, the outer end of which carries a contact button 66. Adjacent the center arbor, rotor 62 is provide-d with a'cam surface 63 adapted to engage the corresponding cam '60 on the third arbor rotor 44. Rotor 62 is provided with a hub 70 having the same outer diameter as a similar hub 72 formed on the center arbor. Over these two hubs are slipped the ends of a helical spring clutch 74 which permits free relative movement between the two 'hubs in one direction and prevents such free movement in the other direction.

A second 'electro-magnet 76 is mounted in a suitable soft iron frame 78 that is in turn secured to but insulated from the plate structure of the motor. Positioned adjacent the coil 80 of the elec-tro-magnet as best seen in FIGURE 2 is an elongated armature 82 of soft iron having a pair of pivot pins such as 84 journalled in the upper and lower elements of the frame. The armature 82 is provided with a shorter broad arm 86 being of a width such that it nearly closes the gap between the upper and lower elements of the frame 78 and a long narrow arm 88 carrying a contact button 90. Positioned between the upper and lower elements of the frame is a cylindrical metal spacer 94. A leaf spring 92 is riveted at one end as shown at 93 to the longer arm of the armature and the other endof the leaf spring bears against spacer Leaf spring 5 2 acts as a bias spring urging the shorter arm of'armature 82 away from core 1M) and against the other side of the spacer. 'Core piece additionally acts as a stop to limit armature movement when the coil 80 is energized.

A main spring 162 is connected by a suitable friction washer 104 to the post 56 on plate 36. The other end of main spring 162 is connected to the center arbor rotor 62. Supported on plate 22 adjacent rotor 62 by suitable means such as an insulating screw 1% is a stationary or fixed contact 108 located at a preselected height determined by the thickness of insulating spacer element 110. The various supporting plates may be connected together in a conventional manner by posts 112 and 114 and screws such as 116. A friction clutch in the form of a bent spring washer 118 bears against the top of the rotor 44 and is adjusted by pressing washer 120 onto the major diameter of extension 42 of third arbor 20.

In operation the coil 80 of electro-magnet 76 is energized when the contact 50 on rotor 44 engages the contact 90 on armature 82. This completes a circuit which may be traced from power supply lead 96 to insulated coil input terminal 97, through the coil 80, short lead 98, spring 92, armature 82, thence through the contacts 90 and 50 and through rotor 44 to the grounded frame of the timing motor. Electro-magnet 30 is connected to the common source the other side of which is grounded through the contacts 66 and 108.

When coil 80 is energized, it attracts the shorter arm 86 of the armature, thus causing the long arm 88 to swing through a similar arc. As the long arm swings, the armature contact button 90 pushes the rotor by means of button 50 imparting a rotary motion to the rotor. Further movement of the armature is prevented by core piece 100 at the end of the coil, but the rotor 44 continues to move under the influence of inertial forces. The continued. movement of the rotor 4'4 acts to break the electrical circuit between contacts S and 90. However, the rotor continues to move in a direction such as to wind the main spring 102.

Winding of the main spring is accomplished by the fact that the momentum of the rotor 40 causes the cam surface 60 of the rotor to engage the cam surface 68 of the second rotor 62. t This causes the second rotor 62 to be driven backwards in a clockwise direction in FIGURE 1, such as to wind main spring 102.

When the energy stored in the rotor 44 has been exhausted by transfer through the engaging cam surfaces to the main spring the latter spring tends to return the center wheel rotor 62 to its rest position. At this time the spring clutch 74 between the hubs 70 and 72 engages and a driving torque is applied to the train 16 by way of the center arbor 18 and its wheel. The center wheel drives the third pinion and through it the third wheel and arbor.

As explained, the third wheel rotor 44 is so mounted on the third arbor 20 as to freely rotate about that arbor. That freedom of rotation is, however, deliberately reduced to a slight extent by the friction clutch 118 interposed between the'rotor and washer 120 in such a manner that the clutch torque barely sufiices to overcome the inertia of the rotor. Thus, as the third arbor is driven, rotor 44 travels with it. This travel continues as the escapement continues to run until the contacts 50 and 90 again meet, energizing the coil 80 and initiating a new rewind cycle.

In the event that the current input has been interrupted the movement continues to run after contacts 50 and 90 are closed under the influence of the main spring. This is possible because the main springs driving force supplies a sufficient couple to overcome the very light frictional torque produced by the friction clutch 118. Running then continues until the contact 66 on the outer end of second rotor 62 engages the fixed contact 108 attached to the stationary plate 22. This completes a second circuit from the line through the coil of starting electro-magnet -30 traceable through this electro-magnet to the fixed contact 108, through contact 66, rotor 62, main spring 102 and finally to the grounded post 56. When contacts 108 and 66 close, the main spring can no longer drive the train and the motor stops.

When the flow of current in the line is resumed, both electro-magnets 30 and 7-6 are energized simultaneously. The electro-magnetic energy of the electro-magnet 30 is used to pull the balance wheel off center by attraction of the iron slugs on the Wheel. At the same time, the winding coil 80 is energized causing movement of armature 82, thus reinitiating the winding and running cycle.-

This cycle can be regulated within reasonable limits by altering gearing, levers and the like. A typical arrangement is the one shown where neglecting slippage of the clutch, a total running time of two minutes was avail able. The total running time was divided in such a manner that the normal running cycle was approximately one minute from pulse to pulse through electro-magnet 76 and the second minute was utilized for the overrun required to close the second set of contacts, namely those for the starting electro-magnet 30.

FIGURE 3 shows a modified embodiment of the novel timing motor of the present invention .with like parts bearing like reference numerals. In FIGURE 3 the small coil for pulsing the balance wheel is eliminated. The center arbor rotor is not used and the main spring 102 is attached to the third arbor rotor 44 by means of the post 52 and one of the friction washers 104. Likewise, the friction clutch is completely eliminated and the rotor 44 is perfectly free to rotate about the third arbor 20.

Rigidly secured to the third arbor 20 just over the rotor 44 is a disc 120. This disc rotates with the third arbor at all times.

One arm of the rotor 44 carries a pivot post 122 that secures a flat pawl 124 to the rotor. The pawl 124 is free to rotate about the post 122 under the influence of a biasing spring 126 bearing against pin 128 carried by the pawl. This pawl frictionally engages the periphery of the disc fixed to the third arbor. The manner of engagement and the shape of the pawl is such that the force applied by the main spring drives the rotor and thence through the pawl the disc 120, consequently driving the third arbor '20.

As the third arbor rotates under the influence of the main spring, the rotor 44 travels with it carrying the pawl 1 24. At this time, the tip of the pawl is biased in a radial outward direction by the spring 126. This continues until the outward end of the pawl engages an eccentric stop 130 mounted in supporting plate 36. When the tip 125 of the pawl engages stop 130 it is rotated about post 122 against the action of spring 126 and the pawl disengages from disc 120 permitting the rotor 44 to spring forward very rapidly under the influence of the main spring so that the contacts 50 and 90 rapidly close, completing the circuit required to energize the coil of electro-magnet 76. The armature then drives the rotor backwards transferring energy into the main spring. At the limit of backward rotor travel the biasing spring 126 resets the pawl locking the rotor to the third arbor via the pawl and disc 120. Then the motor again runs until the pawl is unlocked, precipitating another contact. For a detailed disclosure of the operation of pawl 124 and its associated structure reference may be had to copending application S.N. 228,994, now Patent No. 3,163,727, filed on even date herewith.

By appropriate balancing of the springs and coils, the system of FIGURE 3 can be applied also at the center arbor or even at the barrel depending upon the length of rewind cycle desired. In the embodiment of FIGURE a lO-beat balance system is utilized to attain self-startmg without the necessity for a second starting electromagnet.

Both embodiments of the present invention illustrate a dial train; this includes four sets of A reverted trains for an overall ratio of to the center arbor. This, of course, can be altered as desired for any type of readout. It is apparent that other types of outputs such as a digital counter may be driven from the output shaft.

From the above, it is apparent that the present invention provides a novel self-starting timing motor which may be used to indicate the cumulative time during which current flows in a monitored circuit. The unit is of relatively simplified construction resembling that of a watch and requires only a minimum amount of modification of only a few of the conventional watch elements.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing de scription, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

1. A timing motor comprising center and third arbors, an escapement including a balance for controlling the rotation of said arbors, a first rotor mounted on said third arbor, a second rotor mounted on said center arbor, a main spring coupled to said second rotor, a one Way clutch coupling said second rotor to said center arbor, gear means coupling said arbors whereby said main spring drives said first rotor by way of said second rotor through said clutch and gear means, an electromagnetic for periodically impulsing said first rotor, cam means coupling said first and second rotors whereby said electromagnet drives said second rotor through said first rotor and said cam means, and means for automatically starting oscillations in said balance.

2. A motor according to claim 1 including a friction clutch coupling said first rotor to said third arbor.

3. A motor according to claim 2 wherein said first rotor carries a first electrical contact, said electromagnet having a movable armature carrying a second contact, engagement of said contacts acting to energize said electromagnet.

4-. A motor according to claim 3 wherein said automatic starting means comprises a second electromagnet, said second rotor carrying a third contact, and a fourth electrical contact positioned in the path of movement of said third contact, engagement of said third and fourth contacts acting to energize said second electromagnet.

5. A timing motor comprising center and third arbors for driving indicating means, an escapement including a balance wheel for controlling the rotation of said arbors, a first rotor mounted on said third arbor, a second rotor mounted on said center arbor, a main spring coupled tosaid second rotor, a one Way clutch coupling said second rotor to said center arbor, gear means coupling said arbors whereby said main spring drives said first rotor by way of said second rotor through said clutch and gear means, an electromagnet for periodically impulsing said first rotor, cam means coupling said first and second rotors whereby said electromagnet drives said second rotor through said first rotor and said cam means, a friction clutch coupling said first rotor to said third arbor, a first contact carried by said first rotor, said.

electromagnet having a movable armature carrying a second contact, engagement of said contacts acting to energize said electromagnet, a second electromagnet, means responsive to energization of said second electromagnet for initiating oscillations in said balance wheel, said second rotor carrying a third contact, a fourth electrical contact positioned in the path of movement of said third contact, engagement of said third and fourth contacts acting to energize said second electromagnet, and means coupling said electromagnets to a common electrical input.

6. A motor according to claim 5 wherein said balance wheel is provided with at least one magnetizable element, and said second electromagnet is positioned adjacent said balance wheel to apply an impulsing force to said element whereby balance wheel oscillations are initiated.

7. A motor according to claim 6 wherein said second electromagnet is provided with a projecting core piece having a tapered end adjacent said balance wheel.

References Cited by the Examiner UNiTED STATES PATENTS 1,133,028 3/1915 Hill 58147 1,188,877 6/1916 Anderson 5828 1,861,228 5/1932 Poole 5841 2,672,724 3/1954 Bueche-Rosse -1 581 2,741,083 4/1956 Sullivan et al. 5885.5 2,978,863 4/1961 Strobel 5879 X LEO SMILOW, Primary Examiner.

JOSEPH P. STRIZAK, Examiner. 

1. A TIMING MOTOR COMPRISING CENTER AND THIRD ARBORS, AN ESCAPEMENT INCLUDING A BALANCE FOR CONTROLLING THE ROTATION OF SAID ARBORS, A FIRST ROTOR MOUNTED ON SAID THIRD ARBOR, A SECOND ROTOR MOUNTED ON SAID CENTER ARBOR, A MAIN SPRING COUPLED TO SAID SECOND ROTOR, A ONE WAY CLUTCH COUPLING SAID SECOND ROTOR TO SAID CENTER ABROR, GEAR MEANS COUPLING SAID ARBORS WHEREBY SAID MAIN SPRING DRIVES SAID FIRST ROTOR BY WAY OF SAID SECOND ROTOR THROUGH SAID CLUTCH AND GEAR MEANS, AN ELECTROMAGNETIC FOR PERIODICALLY IMPULSING SAID FIRST ROTOR, CAM MEANS COUPLING SAID FIRST AND SECOND ROTORS WHEREBY SAID ELECTROMAGNET DRIVES SAID SECOND ROTOR THROUGH SAID FIRST ROTOR AND SAID CAM MEANS, AND MEANS FOR AUTOMATICALLY STARTING OSCILLATIONS IN SAID BALANCE. 